By substitution reactions of the coordinated THF ligands of Re 2(μ-X) 2(CO) 6(THF) 2 by elemental chalcogens (S 8 and red selenium), the complexes Re 2(μ-X) 2(CO) 6(S 8) (X = Br, 1; 1, 2), and Re 2(μ-X) 2(CO) 6(Se 7), (X = I, 3; Br, 4) have been prepared. Binuclear compound 3 was crystallographically established to be a coordination compound of cyclo-heptaselenium, two adjacent selenium atoms of the Se 7 ligand [Se-Se distance, 2.558(3) Å] being bonded to rhenium(I), at an average Re-Se distance of 2.586(3) Å, and the nonbonding ReRe distance being 4.077(3) Å. Spectroscopic evidence of the existence of these chalcogen complexes in solution is reported. The Re 2(μ-X) 2(CO) 6(S 8) complexes undergo S 8 displacement by THF, while the coordinated Se 7 moiety is less readily displaced from 3.
Coordination of cyclo-Octasulfur and cyclo-Heptaselenium to Dinuclear Rhenium(I) Systems
CALDERAZZO, FAUSTO;MARCHETTI, FABIO;
2002-01-01
Abstract
By substitution reactions of the coordinated THF ligands of Re 2(μ-X) 2(CO) 6(THF) 2 by elemental chalcogens (S 8 and red selenium), the complexes Re 2(μ-X) 2(CO) 6(S 8) (X = Br, 1; 1, 2), and Re 2(μ-X) 2(CO) 6(Se 7), (X = I, 3; Br, 4) have been prepared. Binuclear compound 3 was crystallographically established to be a coordination compound of cyclo-heptaselenium, two adjacent selenium atoms of the Se 7 ligand [Se-Se distance, 2.558(3) Å] being bonded to rhenium(I), at an average Re-Se distance of 2.586(3) Å, and the nonbonding ReRe distance being 4.077(3) Å. Spectroscopic evidence of the existence of these chalcogen complexes in solution is reported. The Re 2(μ-X) 2(CO) 6(S 8) complexes undergo S 8 displacement by THF, while the coordinated Se 7 moiety is less readily displaced from 3.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.